Salivary biomarkers as a non-invasive diagnostic tool for gastric cancer: a systematic review and meta-analysis.

Abstract

Background: Gastric cancer (GC) remains a leading cause of cancer-related mortality worldwide, with an average survival of just 12 months. Its aggressive nature and nonspecific symptoms often lead to late-stage diagnosis. Current diagnostic methods rely heavily on esophagogastroduodenoscopy, which is invasive and costly. Saliva-based biomarkers have emerged as a promising noninvasive approach for GC diagnosis, although their clinical applicability remains uncertain.

Research design and methods: We performed a systematic search in PubMed, Scopus, and Web of Science to identify studies evaluating saliva-based diagnostics for GC. Pooled sensitivity and specificity were calculated with 95% confidence intervals using RStudio version 4.2.3.

Results: Eleven studies involving 1,119 patients (760 with GC) were included. In the GC group 63.8% were male and biomarkers vary between studies. The pooled sensitivity was 86.3% (95% CI: 0.76-0.93; I² = 82%), and specificity was 85.5% (95% CI: 0.79-0.91; I² = 19%). The summary ROC curve had an AUC of 87.6%, with a normalized partial AUC of 67.2%.

Conclusion: Salivary biomarkers show strong potential for noninvasive GC early detection. Which represents a significant opportunity to change the natural history of gastric cancer. However, due to significant variability in biomarkers utilized, more homogenous studies are needed to better address the question.